Meteorological variables such as temperature, wind speed, wind directions, and Planetary Boundary Layer (PBL) heights have critical implications for air quality simulations. Sensitivity simulations with five different PBL schemes associated with three different Land Surface Models (LSMs) were conducted to examine the impact of meteorological variables on the predicted ozone concentrations using the Community Multiscale Air Quality (CMAQ) version 4.5 with local perspective. Additionally, the nudging analysis for winds was adopted with three different coefficients to improve the wind fields in the complex terrain at 4-km grid resolution. The simulations focused on complex terrain having valley and mountain areas for ozone SIPs (State Implementation Plans). The ETA M-Y (Mellor-Yamada) and G-S (Gayno-Seaman) PBL schemes were identified as favorite options and promote O3 formation causing the higher temperature, slower winds, and lower mixing height among sensitivity simulations in the area of study. It was found that PX simulation did not always give optimal meteorological and CMAQ model performances at mountain sites. The results of nudging analysis for winds with three different increased coefficients’ values (2.5, 4.5, and 6.0 x 10-4 per second) over seven sensitivity simulations show that the meteorological model performance was enhanced due to improved wind fields, indicating the FDDA (Four Dimensional Data Assimilation) nudging analysis can improve model performance considerably at 4-km grid resolution. Specifically, the sensitivity simulations with the coefficient value (6.0 x 10–4) yielded more substantial improvements than with the other values (2.5 and 4.5 x 10-4). Hence, choosing the nudging coefficient of 6.0 x 10-4 per second for winds in MM5 may be the best choice to improve wind fields as an input, as well as, better model performance of CMAQ in the complex terrain area. The sensitivity of RRFs (Relative Response Factors) to the PBL scheme may be considerably significant with about 1-3 ppb in difference in determining whether the attainment test is passed or failed. Finally, a finer grid resolution was necessary to evaluate and access of CMAQ results for giving a detailed representation of meteorological and chemical processes in the regulatory modeling.

Esta tesis constituye un estudio empírico de la privatización de la seguridad social en Perú, con énfasis sobre consumo, ahorro y bienestar. El primer capítulo describe la reforma y la posiciona como un valioso caso de estudio. El segundo evalúa el efecto de la privatización sobre el bienestar de los ancianos y sus dependientes inmediatamente después de la reforma, cuando la seguridad social migraba de un estado estacionario a otro. Se encuentra un efecto positivo, aunque el impacto mayor no fue experimentado ni por los hogares más pobres ni por los hogares de mayor edad. El tercero, en lugar de evaluar la reforma, utiliza la variabilidad provista por ésta para responder una antigua pregunta económica: hasta qué punto el ahorro de pensiones compensa el ahorro voluntario. Se encuentra que, por cada dólar de seguro provisto por el sistema de pensiones, el ahorro voluntario decrece entre 70 centavos y un dólar. / This thesis is an empirical study of the privatization of social security in Peru, with a particular emphasis on consumption, saving and welfare. The first chapter provides a general description of the reform and positions it as a valuable study case. The second chapter evaluates the effect of the privatization on the well-being of the elderly and their dependents immediately after the reform, when social security was moving from a steady state to the other. It concludes that the effect was positive, although the larger impact was experienced neither by the poorest households nor by the oldest households. The third chapter, instead of evaluating the reform, uses the variability provided by the reform to analyze an old economic question: to what extent pension saving crowds out voluntary saving. It finds that for every dollar of insurance provided by the pension system, voluntary savings decrease by 70 cents to one dollar.

Developed countries are striving to achieve a cm geoid model. Most developing countries/regions think that the situation in their areas does not allow even a few decimetre geoid model. GNSS, which provides us with position, is one of the greatest achievements of the present time. Conversion of ellipsoidal height to orthometric height, which is more useful, requires an accurate geoid model. In spite of the sparse terrestrial gravity data of variable density, distribution and quality (a typical situation in developing countries), this study set out to develop as accurately as possibly achievable, a high quality geoid model of Tanzania. Literature review of three more preferred geoid methods came to a conclusion, that the Royal Institute of Technology of Sweden (KTH) method of least squares modification of Stokes formula (LSMS) with additive corrections (AC) is the most suitable for this research. However, even with a good method, the accuracy and the quality of a geoid model depend much on the quality of the data. In this study, a procedure to create a gravity database (GDB) out of sparse data with varying density, distribution and quality has been developed. This GDB is of high density and full coverage, which ensures presence of high and low gravity frequencies, with medium frequencies ranging between fair and excellent. Also an alternative local/regional Global Gravitational Model (GGM) validation method based on quality terrestrial point surface gravity anomaly has been developed. Validation of a GGM using the new approach of terrestrial point gravity and GPS/Levelling, gave the same results. Once satisfactorily proved, the method has extra advantages. The limits of Tanzania GDB (TGDB) are latitudes 15 ° S to 4 ° N and longitudes 26 ° E to 44 ° E . Cleaning and quality control of the TGDB was based on the cross validation (XV) by the Kriging method and Gaussian distribution of the XV residuals. The data used in the LSMS with AC to develop a new Tanzania gravimetric geoid model 2008, TZG08, are 1′ ×1′ clean and statistically tested surface gravity anomalies. 39,677 point gravity in land and 57,723 in the ocean were utilised. Pure satellite ITGGRACE03S GGM to degree 120 was used to determine modification parameters and long-wavelength component of the geoid model. 3′′ Shuttle Radar Topographic Mission (SRTM) Digital Elevation Model (DEM), ITG-GRACE03S to degree 120 and EIGENCG03C to degree 360 combined GGM qualified to patch the data voids in accordance to the method of this research. TZG08 is referred to Geodetic Reference System 1980 (GRS80), and its extents are latitudes 12 ° S to 1 ° N and longitudes 29 ° E to 41 ° E . 19 GPS/levelling points qualified to assess the overall accuracy of TZG08 as 29.7 cm, and upon approximate removal of GPS and orthometric systematic effects, the accuracy of TZG08 is 27.8 cm. A corrector surface (CS) for conversion of GPS height to orthometric height referred to Tanzania National Height Datum (TNHD) has been created for a part of TZG08. Using the CS and TZG08, orthometric height of Mt. Kilimanjaro is re-established as it was in 1952 to be 5,895 m above the TNHD, which is still the official height of the mountain. / <p>QC 20100813</p>